Primary drainage with centrifuge is considered where a core fully saturated with a dense wetting phase is rotated at a given rotational speed and a less dense, non-wetting phase enters. The displacement is hindered by a positive drainage capillary pressure and equilibrium is approached with time. We present general partial differential equations describing the setup and consider a multi-speed drainage sequence from one equilibrium state (at a given rotational speed) to the next.

By appropriate simplifications we derive that the process is driven by the distance from equilibrium state as described by the capillary pressure at the inner radius and position of the threshold pressure (transition from two to one-phase) from their equilibrium values.

Further, an exponential solution can describe the transient production phase.

Using representative input saturation functions and system parameters we solve the general equations using a commercial software (Sendra v2016.1) and compare with the predicted exponential solutions. It is seen that the match is excellent and that variations in time scale are well captured.

The rate is slightly underestimated at early times and overestimated at late times, which can be related to changes in total mobility during the cycles for the given input.


Article metrics loading...

Loading full text...

Full text loading...


  1. Andersen, P.Ø., Evje, S. and Kleppe, H.
    [2014], A Model for Spontaneous Imbibition as a Mechanism for Oil Recovery in Fractured Reservoirs, Transport in Porous Media, 101 (2), 299–331. DOI: 10.1007/s11242‑013‑0246‑7
    https://doi.org/10.1007/s11242-013-0246-7 [Google Scholar]
  2. Andersen, P.Ø., Evje, S. and Hiorth, A.
    [2015], An Analytical Model for Imbibition Experiments with Porous Plate, In: IOR 2015 - 18th European Symposium on Improved Oil Recovery, 14–16 Apr, Dresden, Germany. DOI: 10.3997/2214‑4609.201412112
    https://doi.org/10.3997/2214-4609.201412112 [Google Scholar]
  3. Anderson, W.G.
    [1987], Wettability Literature Survey - Part 4: Effects of Wettability on Capillary Pressure, Journal of Petroleum Technology, 39 (10), 1283–1300. DOI: 10.1007/s11242‑013‑0246‑7
    https://doi.org/10.1007/s11242-013-0246-7 [Google Scholar]
  4. Bentsen, R.G., Anli, J.
    [1976], A New Displacement Capillary Pressure Model, J Can Pet Technol, 15 (3). DOI: 10.2118/76‑03‑10
    https://doi.org/10.2118/76-03-10 [Google Scholar]
  5. Donaldson, E.C., Thomas, R.D. and Lorenz, P.B.
    [1969], Wettability Determination and Its Effect on Recovery Efficiency, SPE Journal, 9 (1), 13–20. DOI: 10.2118/2338‑PA
    https://doi.org/10.2118/2338-PA [Google Scholar]
  6. Fleury, M., Doevle, M. and Longeron, D.
    [1997], Full Imbibition Capillary Pressure Measurements on Preserved Samples using the Micropore Membrane Technique, In: The International Symposium of the Society of Core Analysts, Calgary, Canada. SCA 1997–16.
    [Google Scholar]
  7. Fleury, M., Egermann, P. and Goglin, E.
    [2000], A Model of Capillary Equilibrium for the Centrifuge Technique, In: The International Symposium of the Society of Core Analysts, Abu Dhabi. SCA 2000–31.
    [Google Scholar]
  8. Forbes, P.L.
    [1997], Centrifuge Data Analysis Techniques: An SCA Survey on the Calculation of Drainage Capillary Pressure Curves from Centrifuge Measurements, In: The International Symposium of the Society of Core Analysts, Calgary, Canada. SCA 1997–14
    [Google Scholar]
  9. [2000], The H&B Boundary Condition in Centrifuge Pc Experiments (or why there is no Experimental Evidence that the Pressure Field Model ever Failed), In: The International Symposium of the Society of Core Analysts, Abu Dhabi. SCA 2000–19
    [Google Scholar]
  10. Hagoort, J.
    [1980], Oil Recovery by Gravity Drainage, SPE Journal, 20 (3), 139–150. DOI: 10.2118/7424‑PA
    https://doi.org/10.2118/7424-PA [Google Scholar]
  11. Hammervold, W.L., Knutsen, Ø., Iversen, J.E. and Skjæveland, S.M.
    [1998], Capillary Pressure Scanning Curves by the Micropore Membrane Technique, Journal of Petroleum Science and Engineering, 20 (3), 253–258. DOI: 10.1016/S0920‑4105(98)00028‑X
    https://doi.org/10.1016/S0920-4105(98)00028-X [Google Scholar]
  12. Hassler, G.L. and Brunner, E.
    [1945], Measurements of Capillary Pressures in Small Samples, Petroleum Transactions AIME, 160 (1), 114–123. DOI: 10.2118/945114‑G
    https://doi.org/10.2118/945114-G [Google Scholar]
  13. LenormandR. and Delaplace, P.
    [1996], Can we Really Measure the Relative Permeabilities using the Micropore Membrane Method, In: The International Symposium of the Society of Core Analysts, Montpellier, France. SCA 1996–37.
    [Google Scholar]
  14. Purcell, W.R.
    [1949], Capillary Pressures - their Measurement using Mercury and the Calculation of Permeability therefrom, Petroleum Transactions AIME, 1 (2), 39–48. DOI: 10.2118/949039‑G
    https://doi.org/10.2118/949039-G [Google Scholar]
  15. Ruth, D.W. and Chen, Z.A.
    [1995], Measurement and Interpretation of Centrifuge Capillary Pressure Curves - The SCA Survey Data, The Log Analyst, 36 (5), 21–33.
    [Google Scholar]

Data & Media loading...

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error